He had been missing less than half an hour while his mother, April Carpenter, 24, was studying at her home in the 2200 block of West Boston Street, Sgt. Joe Favazzo said. It was about 11 a.m.

In that space of time, the blond, chubby-cheeked toddler somehow slipped out of the house, climbed into his mother's parked car and died, police said. The hospital recorded his core temperature at 108 degrees.

"It appears as if the child did just that: came into the car to play," Favazzo said outside the one-story brick home in a neighborhood filled with young children.

Carpenter, who one neighbor said worked at Southwest Ambulance and was studying to be an EMT, panicked.

"I heard her crying from here," said Mireya Valverde, who lives across the street. "She was crying and screaming."

"She was very scared and freaked out," said next-door neighbor Arizbe Rosas, 17.

Several neighbors helped her look for the child, focusing on backyards and pools. Within five fruitless minutes, Carpenter called 911, Favazzo said.

The officer who arrived at the scene found the boy sprawled in the front seat of Carpenter's car, Favazzo said. He was unresponsive, and pronounced dead at an area hospital.

Police are continuing the investigation of Jaden's death, Favazzo said.

Neighbors in the close-knit community, where kids flow from one house to the next, were devastated by the tragedy. Carpenter's parents had lived in the house for nearly 27 years before moving out three months ago, when Carpenter moved in with Jaden, they said.

"It was a total accident," said Kim Golding, 37, who lives a few houses down. "I know it was. Why did it have to happen? But it did.

"You think about the pools but not the cars. Like my car doors are unlocked right now."

"It is not her fault what happened," said neighbor Lily Valdez, 37, who has five children. "It could happen to anybody. The lesson is if you don't see your kid for a minute, look for him."

Often, boys go into cars to push buttons and play with the wheel like they see their parents do, said Favazzo and Janette Fennell, president of KidsAndCars.org.

"A lot of times, they get unlucky and the doors are locked. Or the heat overtakes them and they pass out," Fennell said.

Jaden is the second child to die in Arizona this year in a parked vehicle, and one of 22 who have perished nationwide, said Fennell, whose organization tracks such statistics.

On June 27, a 21-month-old Phoenix child died from heat-related causes when she was left in the backseat of her family's vehicle for nearly 2 1/2 hours. Temperatures that day soared to 108 degrees.

Golding said of Carpenter, "my heart aches for that mom. I hugged my daughter and said, 'Thank goodness you are still here.' "